A Michael Ricketts' header three minutes into added time earned 10-man Walsall a 1-1 draw that extends their unbeaten run to 13 games.
Port Vale had looked set to pick up the points thanks to Marc Laird's strike in the 12th minute.
The on-loan midfielder drove in from 25 yards for his first league goal.
Walsall had Daniel Fox sent off for a second yellow card, but Ricketts saved them with a header from a cross by former Vale full-back Rhys Weston.
Port Vale: Anyon, McGregor, Pilkington, Lowe, Talbot (Miles 35), Laird (Hulbert 36), Harsley, Salmon, McGoldrick, Rodgers, Willock, Miles (Whitaker 45).
Subs Not Used: Martin, Richards.
Goals: Laird 12.
Walsall: Ince, Weston, Gerrard, Dann, Fox, Sweeney (Nicholls 63), Wrack, Bradley, Deeney (Demontagnac 55), Ricketts, Mooney (Sonko 15).
Subs Not Used: Bossu, Roper.
Sent Off: Fox (68).
Booked: Ricketts, Fox, Deeney, Gerrard, Dann.
Goals: Ricketts 90.
Ref: Phil Joslin (Nottinghamshire).